Relationship Between Agriculture and Ecological Deterioration,Restoration and Reconstruction in Loess Plateau Areas of Northwest China

A comprehensive analysis was conducted on the current situation as well as historic succession processor agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of China, several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting 'water conservancy-type ecological agriculture' through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in Northwest China.

Explaining farmers'reluctance to adopt green manure cover crops planting for sustainable agriculture in Northwest China

Green manure cover crops(GMCCs)planting has a potential for mitigating greenhouse gas emissions(GHG)in agroecosystems and provides important ecosystem services,thereby achieving the Sustainable Development Goals(SDGs)stipulated by the United Nations.However,the advantages of cultivating GMCCs on arable land are not widely recognized.For example,in the whole of China,the GMCCs planting area is less than 3.5%of total arable land.The aim of this study is to explore reasons for the low adoption rate of GMCCs planting.Using best–worst scaling(BWS)approach,farmers ranked their preferred conservation practices including three types of GMCC cropping systems.Taking Gansu Province in Northwest China as a case study,a survey with 276 farmers was conducted.The findings indicated that three factors are related to the low adoption rate of GMCCs:1)farmers preferred improving farmland irrigation facilities and substituting chemical fertilizers with organic rather than planting GMCCs;2)lack of awareness and understanding of government policy on GMCCs and limited access to training courses;3)financial support and subsidies from the government are insufficient.This study provides insights and strategic implications for policymakers on how to further promote GMCCs in the future.

Research on Purification Effect of Jian Lake Zizania latifolia Wetland Lakefront Zone in Northwest of Yunnan Plateau on Nitrogen and Phosphorus of Agricultural Non-point Source

As the main external pollution source of lake,nitrogen and phosphorus from agricultural non-point source make a great contribution to the lake eutrophication pollution.Wetland lakefront zone which plays a key role in externally agricultural non-point source pollution is considered as the biggest barrier for controlling external pollution.In this research,the Jian lake plateau Zizania latifolia wetland lakefront zone was selected for agricultural non-point source pollutions control with the systematic field research,and the lakefront zone was approved to have an effective purification effect on nitrogen and phosphorus from Jinlong River; the theoretical mechanism of lakefront zone removing nutrient was also investigated.Z.latifolia wetland lakefront zone could remove nitrogen and phosphorus from Jinlong River and the removal ratio can reach 55.8-62.52% and 59.47-69.81% respectively.So,we can indicate that the Jian Lake plateau Z.latifolia wetland lakefront zone had a good effect on controlling agricultural non-point source pollution and protecting the environment.

Resilience, reliability and risk analyses of maize, sorghum and sunflower in rain-fed systems using a soil moisture modeling approach

This paper is aimed at examining the applicability of methods for resilience, reliability and risk analyses of rain-fed agricultural systems from modeled continuous soil moisture availability in rain-fed crop lands. The methodology involves integration of soil and climatic data in a simple soil moisture accounting model to assess soil moisture availability, and a risk used as indicator of sustainability of rain-fed agricultural systems. It is also attempted to demonstrate the role of soil moisture modeling in risk analysis and agricultural water management in a semi-arid region in Limpopo Basin where rain-fed agriculture is practiced. For this purpose, a daily-time step soil moisture accounting model is employed to simulate daily soil moisture, evaporation, surface runoff, and deep percolation using 40 years (1961-2000) of agroclimatic data, and cropping cycle data of maize, sorghum and sunflower. Using a sustainability criterion on crop water requirement and soil moisture availability, we determined resilience, risk and reliability as a quantitative measure of sustainability of rain-fed agriculture of these three crops. These soil moisture simulations and the sustainability criteria revealed further confirmation of the relative sensitivity to drought of these crops. Generally it is found that the risk of failure is relatively low for sorghum and relatively high for maize and sunflower in the two sites with some differences of severity of failure owing to the slightly different agroclimatic settings.

Systematic Analysis and Optimization of the Agricultural Structure in Ethnic Regions in Northwest Sichuan Province

Based on introducing the basic conditions of the ethnic regions in northwest Sichuan Province,the thesis analyzes its agricultural development status,which can be classified into two aspects--rich natural resources and slow agricultural economic growth.Through the analysis on the agricultural structure of northwest Sichuan Province,it is found that the production efficiency and economic benefits of crop planting in this region are low,animal husbandry,as a major industry in pastoral region,sees high production efficiency,the agricultural production is still at the resource-oriented stage;its agricultural structure is still the farming-pastoral structure relying mainly on animal husbandry,planting is dominated by crop planting and potato planting,animal husbandry mainly produces dairy and beef;the ethnic regions in northwest Sichuan Province is endowed with the advantages to grow crops,beans and fruits as well as to produce beef,mutton and milk,among which,three industries,say fruit,beef and dairy are with increasing location quotient and gradually strengthening industrial comparative advantage,while the location quotient of the other industries is declining and their industrial comparative advantages are more stable.In order to promote the agriculture in northwest Sichuan Province to develop in breadth and depth,the thesis proposes the following measures and suggestions:the first one is to adhere to the development strategy of modern animal husbandry;the second is to appropriately improve the proportion of economic crops;the third is to accelerate the development of green food processing industry.

涉农高校科技赋能“土特产”升级发展的实践探索--以西北农林科技大学助推陕西富平柿子产业发展为例

产业振兴是乡村振兴的重中之重,也是实际工作的首要切入点。我国乡村生态类型多样、资源禀赋各异,独具特色和优势的乡土传统产业众多,借助新科技的力量,加快“土特产”升级发展,对促进区域乡村振兴和经济社会高质量发展意义重大。文章以西北农林科技大学科技助推陕西富平柿子产业升级发展为例,介绍了富平柿子产业发展概况,阐述了西北农林科技大学科技助推陕西富平柿子产业升级发展的主要举措与取得的成效,并总结了实践经验,以期为新时期涉农高校和科研院所精准服务区域乡村振兴提供借鉴。

创新价值链视角下西北地区农业技术创新效率研究

提高农业技术创新效率对驱动西北地区农业高质量发展,乃至实现我国农业现代化战略目标意义重大。文章通过构建农业技术创新效率测算模型和Tobit回归模型,对西北地区农业技术创新效率进行评价分析,并探究其主要影响因素。研究表明:西北地区整体农业技术创新效率值较低,且区域差距明显;政府支持力度、涉农企业技术创新水平、农业生产力发展水平均正向影响农业技术创新效率;农村劳动力素质无显著影响;农村经济发展水平对农业技术创新效率具有显著抑制作用。西北地区政府应采取有效措施,提升农业技术创新效率。

中国西北地区农业生态效率时空分异及影响因素研究

立足资源禀赋和发展阶段因地制宜提高农业生态效率是农业强国建设的必由之路。在借助非期望非径向SE-SBM模型测度2010—2020年中国西北地区市域尺度农业生态效率的基础上,综合应用差异系数、Dagum基尼系数、全局趋势分析、全局莫兰指数和空间误差模型等指标和方法探讨了中国西北地区农业生态效率时空分异特征及影响因素。结果表明:(1)2010—2020年中国西北地区农业生态效率的中位数在波动中由0.512上升至1.001,年均增长率约为6.93%,且市域间农业生态效率的差异程度呈现出缩小的态势。(2)中国西北地区农业生态效率呈现出梯次性的圈层空间分布特征,投影趋势线在南北方向呈现出“U型”特征,而东西方向则是在由西向东平滑上升的过程中逐渐显现出“倒U型”特征。(3)劳均耕地面积、农村居民人均可支配收入、城镇化水平对中国西北地区农业生态效率产生正向影响,而农业机械密度与化肥使用强度则对该地区农业生态效率产生负向影响。

浅析晋西北莜麦生产现状及发展前景

莜麦是山西最具地方特色的杂粮作物之一,但近些年受市场经济及耕作方式的影响,种植效益不好,耕作面积逐年下降。为提升晋西北特色作物莜麦的市场竞争力,针对其生物特性及生产现状,阐述了莜麦有机化生产的前景及优势。

西北干旱区农业生产适宜性评价与布局优化研究——以武威市为例

农业生产适宜性评价是新时期国土空间规划中农业空间优化调整的前提,是科学划定农业空间和永久基本农田的必要依据,对保障国家粮食安全和生态安全具有重要意义。本文以武威市作为西北干旱典型区,运用GIS软件,分别对农业生产的必要要素——土地资源、水资源和气候条件进行了评价分析,并进行模型集成,形成评价结果。在对农业生产适宜性评价结果分析的基础上,提出武威市农业生产布局优化思路及具体措施,探讨农业生产适宜性对于国土空间规划的支撑作用。

戴季陶与中国西北高等农林教育

训政时期,戴季陶曾三次赴西北考察。在1932年,戴季陶与于右任,张继等国民党高层人士提出创办西北农林专科学校。1934年西北农专建校,戴季陶参与学校的选址、农专及附设机构设置,筹备师资和编制学系。戴季陶提出并参与筹办的民国西北农林专科学校,为这一时期的中国培养了一大批农林业人才,学校延续至今演变成西北农林科技大学,对中国西北高等农林教育有着积极影响,为当今的农林现代化和农林科技事业提供历史的借鉴。

中国西北地区气候变暖对农业的影响

选取西北地区资料年代较长的171个地面测站1961～2003年日平均气温资料,计算历年≥0℃、≥10℃积温和<0℃负积温,深入研究西北地区热量资源对气候变暖的响应及其对农业生产的影响。结果表明:1987～2003年比1961～1986年的平均值明显增高,尤以最低气温增幅最大,这说明最低气温的变化比最高气温的变化更敏感,西北地区气候变暖主要来自最低气温升高的贡献。冬季升温幅度大于夏季,<0℃负积温绝对值明显减少。西北地区20世纪80年代后期气候明显变暖,热量资源增加,喜温作物面积扩大,越冬作物种植区北界向北扩展,对牧区牲畜越冬度春有利。西北地区气候变暖对农业的负面影响大于正面影响。

全球气候变化对我国西北地区农业的影响

在比较系统总结全球气候变化对我国西北地区农业影响的主要研究成果的基础上,揭示了我国西北地区现代气候变化对全球气候变暖响应的基本特征,阐述了现代气候变化对土壤水分、地表蒸发和作物气候生产力的影响规律;并且比较全面地概括了西北地区冬、春小麦、玉米、马铃薯、冬油菜、棉花、胡麻、牧草、葡萄等9种主要农作物的生长发育、病虫害、种植面积、气候产量以及畜牧业活动等对气候变化的响应特征,发现气候变化对农业生产过程的影响利弊皆存,而且不同农作物对气候变化的响应特征差异较大。研究对西北地区农业生产具有比较重要的科学指导意见。

植被状态指数监测西北干旱的适用性分析

利用1982—2003年22年逐月GIMMS 8 km分辨率的NDVI数据和西北地区138个气象台站同期月降水数据,分析了植被状态指数(VCI)对西北地区历史干旱的监测能力。根据西北气候和植被类型的特点,选取雨养农业区、灌溉农业区和青藏高原高寒草原区为典型研究区域,研究了VCI对不同地区气象干旱的监测能力,并对VCI监测干旱的适应性进行分析。结果表明:VCI可以较好地反映西北大部分历史干旱的空间分布及其演变特征。对于不同的气候区域,VCI监测干旱的效果存在一定的差别。对于西北东部的雨养农业区,VCI能够较好地反映降水的盈亏对植被影响,是监测这一地区干旱的有效指标;在西北区西部的灌溉农业区,VCI基本不能反映这一地区降水的多寡,不能作为这些地区气象干旱监测的指标;VCI也不能反映青藏高原高寒草原区降水的亏缺,不能作为监测这些地区气象干旱的指标;在极涡干旱的戈壁、沙漠地区VCI会出现虚假的高值。

西北地区农林牧业生产及农业结构调整对全球气候变暖响应的研究进展

受西北地区现代气候变化呈现冬暖夏干的影响，甘肃黄土高原200cm深土壤贮水量呈减少趋势，适宜农作物生长时段减少2—3月．黄土高原作物气候生产力呈下降趋势，年递减率为10．45kg·hm^-2，暖干型和冷干型气候对作物生长非常不利，减产为4．3％～27．1％．对畜牧业的影响利弊共存，使牧区草场产草量和质量以及生产力下降；但牲畜死损率明显降低，幼畜成活率明显增加；牲畜抓膘育肥利弊因素相当，牲畜肉量呈波动式变化．小陇山森林资源呈减少趋势，90年代最为严重．在全球变暖的气候变化下，需要农林牧业结构发生重大调整，提出了甘肃省以及祁连北坡、陇东、陇东南和陇南等4个具有代表性的重点地域的农林牧业种植结构调整发展战略与优化方案．其研究结果为西北地区农林牧业安全生产、趋利避害、减轻不利影响提供科学的指导意见．

西北地区设施农业研究现状及存在的问题

本文以西北地区设施农业产业发展现状为基础,阐述了西北地区设施农业的总体发展概况,概述了设施农业新能源的综合开发利用、新型日光温室的研制及保温性能的优化等方面的研究进展。针对西北地区设施农业的发展与研究现状,提出了当前西北地区设施农业中存在的一系列问题与建议,以期为今后一个时期西北地区设施农业的进一步发展提供参考。

中国西北地区近43年降水资源变化对农业的影响

选取西北地区资料年代较长的171个地面测站1961～2003年历年降水量,深入研究了西北地区降水资源变化特征及其对农业生产的影响。结果表明:年降水量、越冬作物生育期降水量、春小麦生育期降水量和秋作物生育期降水量,1987～2003年与1961～1986年相比,西部增多,东部减少,分界线与黄河走向基本一致。西部呈增多变化趋势,洪水事件频数增多,可利用水资源略有增加,对农业的正面影响增大。东部呈减少变化趋势,干旱频繁发生,尤其是极端干旱事件频数增多,可利用降水资源更加紧缺,对农业的负面影响增大。西北地区冬季降水普遍增多,对土壤保墒、作物安全越冬和春播有利;但是,牧区雪灾增多,影响牲畜安全过冬。

西北地区特色农业发展潜力与定位分析

西北地区地域广阔,地貌类型多样,具有发展特色农业的比较优势。然而,受自然条件、资源禀赋、市场容量、增收潜力、粮食安全与生态环境等因素的综合制约,不宜高估西部特色农业发展的潜力。从区域宏观层面进行西北特色农业发展潜力的客观评价,对于利用有限资金,适度发挥特色农业资源的比较优势,科学协调农村脱贫致富与生态环境保护关系,促进区域社会经济可持续发展,具有重要的战略意义。

30年来我国农业气象灾害变化趋势和分布特征

利用1979-2008年的统计数据分析了我国近30年来农业气象灾害的时间变化趋势和空间分布特征。结果表明:(1)1979-2008期间,我国农业气象灾害的灾情日趋严重,农业气象灾害总成灾面积和成灾比率都呈增加趋势;各类灾害中,旱灾和霜冻成灾面积和成灾比率呈增加趋势,风雹成灾面积和成灾比率变化不大呈略微下降趋势,而1989-1998年段水灾严重。(2)旱灾成灾面积在总成灾面积中所占比例最大(约占总成灾面积的1/2),其次是水灾(约占总成灾面积的1/4),再次是风雹,而霜冻成灾面积最小。(3)在区域分布方面,旱灾灾情华北地区最为严重,其次是东北,再次是西北;水灾和旱灾的轻重程度往往是一个此消彼长的关系,华中的水灾最严重,其次为华东、华南和西南;风雹灾情的轻重程度在我国的分布也有较强的区域性,华北、西北和东北是风雹的重灾区;霜冻分布各区域差异较小,西北和华中的灾情相对较重。

发展苜蓿草产业促进西北旱区农业结构调整

西部大开发进一步深入,增加西北地区农民的收入已成为全面实现小康战略目标的关键因素,调整农业产业结构,促进农民和农业增收已成为当前西部开发的首要问题。本文通过对西部地区苜蓿草产业发展现状和潜力的分析,论证了苜蓿草产业在西北旱区农业结构调整中的潜力、地位和作用,提出通过发展苜蓿草产业,推进西部地区农业结构战略性调整,促进农村经济的发展,将成为西北地区经济创新和农业增收的必然选择。